OLED display has attracted more and more attentions due to such unique advantages as rapid response, fully-solid state and self-luminescence. In addition, the OLED display may be applied to various fields, e.g., flexible display, transparent display and micro-display.
Currently, a full-color display effect of the OLED display may be achieved in two modes. In a first mode, light-emitting materials may be evaporated directly using a Fine Metal Mask (FMM) so as to form red (R), blue (B) and green (G) subpixels. In a second mode, the color display effect may be achieved using white-OLED (WOLED) plus a color filter. In the case of evaporating the light-emitting materials using the FMM to form the R, G and B subpixels, it is unnecessary to provide any color filter, so no brightness loss may occur. In addition, the light-emitting materials have relatively high luminous efficiency, so it is able to acquire the display with a large color gamut and a large brightness value.
However, due to the limitation of the FMM precision, it is merely able to manufacture the OLED display having a Pixel Per Inch (PPI) value up to 400 through the FMM in the related art. Currently, there are more and more applications where a higher PPI value is required. For example, in the field of micro-display, it is unable for the 400PPI display to meet the requirements of human eyes. Hence, there is an urgent need to find a scheme for manufacturing the OLED display with a higher PPI value through the FMM.